Cylindrical thermoelectric power generation system structure and optimization method

Abstract

This invention belongs to the field of automotive exhaust waste heat recovery technology, and particularly relates to a cylindrical thermoelectric power generation system structure and optimization method. The device includes: a heat exchanger, a flow pipe, a hot-end distributor, a cold-end distributor, and a thermoelectric module; the outer wall of the heat-conducting flow pipe has several fins; the heat-conducting flow pipe has a hollow channel along the axial direction of the heat exchanger; the fins are spaced circumferentially along the flow pipe to form a heat-conducting channel between adjacent fins. By setting fins inside the heat exchanger, the heat conduction performance of the heat exchanger is enhanced, and heat is conducted to the hot-end distributor to enable the thermoelectric module to generate electricity. The hollow channel and heat-conducting channel are used to balance the heat transfer and pressure drop of the exhaust gas. A baffle is set at the end of the flow pipe to redirect the exhaust gas flow, thereby enhancing the heat transfer and temperature uniformity of the rear region.

Description

Technical Field

[0001] This invention belongs to the field of automotive exhaust waste heat recovery technology, and particularly relates to a cylindrical thermoelectric power generation system structure and optimization method. Background Technology

[0002] Energy conservation, environmental protection, and low carbon emissions have become global themes of exploration. With the proposal of "carbon peaking and carbon neutrality" goals and the emergence of the problem of low energy utilization in automobiles, researchers have gradually explored the recycling and treatment of vehicle exhaust and the utilization of waste. In traditional internal combustion engine vehicles, about 30% of the energy released by the combustion of petroleum fuel is utilized to convert into the kinetic energy of the vehicle, while about 40% of the energy is emitted into the atmosphere with the exhaust. This wastes most of the energy and causes serious environmental pollution.

[0003] Thermoelectric power generation is a new type of green and environmentally friendly energy technology that uses the Seebeck effect to directly convert heat energy into electrical energy. It converts low-grade waste heat energy in exhaust gas into high-grade electrical energy for storage in car batteries or for use by vehicle electrical appliances.

[0004] Recent advances in thermoelectric materials have propelled thermoelectric power generation systems (TEGs) to the forefront as a viable technology for utilizing vehicle waste heat. TEGs possess significant appeal due to their stationary design, quiet operation, and low maintenance requirements. Extensive research has led to the development and fabrication of various TEG prototypes, demonstrating their potential for practical applications. These advancements highlight the crucial role of TEGs in improving energy efficiency and promoting automotive sustainability.

[0005] However, although traditional thermoelectric power generation technology can convert heat energy into electrical energy, the high speed of automobile exhaust means that most of the heat in the exhaust cannot be fully utilized before it is discharged, resulting in low thermoelectric conversion efficiency and poor practical performance.

[0006] Therefore, it is urgent to design a cylindrical thermoelectric power generation system structure and optimization method to solve the technical problem that most of the heat in the exhaust gas cannot be fully utilized before being discharged, resulting in low thermoelectric conversion efficiency and poor actual use effect.

[0007] It should be noted that the information disclosed in this background section is only for understanding the background technology of this application concept, and therefore may include information that does not constitute prior art. Summary of the Invention

[0008] This disclosure provides at least one cylindrical thermoelectric power generation system structure and optimization method.

[0009] In a first aspect, the present disclosure provides a cylindrical thermoelectric power generation system structure, including: a heat exchanger, which is hollow inside and suitable for the flow of exhaust gas; A flow pipe is arranged axially inside the heat exchanger; A hot-end distributor is installed on the outer wall of the heat exchanger and corresponds to the flow pipe; A cold-end splitter, which is installed on one side of the hot-end splitter; A thermoelectric module, which is installed between the hot-end splitter and the cold-end splitter; The outer wall of the flow tube has several fins, and the outer ends of the fins are attached to the inner wall of the heat exchanger. The flow pipe has a hollow flow channel along the axial direction of the heat exchanger; The fins are spaced apart circumferentially along the flow tube so that a heat conduction channel is formed between two adjacent fins; Furthermore, when the exhaust gas enters the heat exchanger, the flow pipe and fins guide the heat of the exhaust gas through the heat exchanger to heat the hot end face of the hot end splitter, so that the cold end face of the cold end splitter and the hot end face of the hot end splitter form a temperature difference with the two sides of the thermoelectric module, thereby driving the thermoelectric module to generate electricity. The exhaust gas flows through the hollow flow channel and the heat-conducting flow channel before exiting the heat exchanger to balance the heat transfer and pressure drop of the exhaust gas.

[0010] In one optional embodiment, the heat exchanger has a plurality of flow tubes inside, and at least one of the flow tubes is fitted with a baffle at its tail end, the baffle closing the hollow flow channel of the flow tube. When the exhaust gas flows through the baffle, the baffle blocks the exhaust gas from passing through, so that the exhaust gas can only pass through the heat-conducting flow channel outside the flow pipe corresponding to the baffle, thereby guiding the exhaust gas to enhance local heat transfer and temperature uniformity.

[0011] In one alternative embodiment, a plurality of flow pipes are arranged at equal intervals along the interior of the heat exchanger so that a bypass channel is formed between two adjacent flow pipes. When the exhaust gas passes through the bypass channel, it can flow between the heat-conducting channel and the hollow channel to reduce exhaust gas pressure loss and optimize heat transfer efficiency.

[0012] In one optional embodiment, a cooling pipe is provided on the outside of the heat exchanger, and the cooling pipe is adapted to circulate coolant. The cold-end splitter has a cooling channel inside, and the cooling channel is connected to the cooling pipe.

[0013] In one alternative implementation, the cooling channel circumferentially covers the cold end face of the cooling distributor.

[0014] In one optional embodiment, the cooling channel has an inlet and an outlet at each end; The inlet and outlet are respectively connected to the cooling pipe.

[0015] In one optional embodiment, the thermoelectric module includes a plurality of P-type thermoelectric arms, N-type thermoelectric arms, a metal electrode plate, and two ceramic substrates. The P-type thermoelectric arms and N-type thermoelectric arms are arranged in an array, and the P-type thermoelectric arms and N-type thermoelectric arms are arranged alternately. The two ends of the metal electrode plate are respectively connected to the adjacent P-type thermoelectric arm and N-type thermoelectric arm; The two ceramic substrates are located on both sides of the P-type thermoelectric arm and the N-type thermoelectric arm, respectively, and are attached to the metal electrode plate.

[0016] Secondly, this disclosure also provides an optimization method for a cylindrical thermoelectric power generation system structure, applied to optimize the cylindrical thermoelectric power generation system structure as described above. The optimization method includes the following steps: Step S1: Assemble the cylindrical thermoelectric power generation system structure and install several flow pipes at equal intervals along the axial direction inside the heat exchanger; Step S2: Based on its structural configuration and symmetrical heat transfer characteristics, a calculation model is established for a local structure to improve efficiency. Step S3: Set boundary conditions to simulate the theoretical operating state; Step S4: Install baffles at the tail end of the flow tube at different positions in sequence, establish corresponding control groups, calculate the net output power of each control group, compare the calculation results, and obtain the optimal baffle installation position. Step S5: Set the height ratio of the fins to the hollow flow channel to R, and replace the fins and flow tubes with different R values ​​in sequence to establish corresponding control groups. Calculate the net output power of each control group, compare the calculation results, and obtain the optimal height ratio R of the fins to the hollow flow channel.

[0017] In one alternative implementation, the R-value control groups are set to 0.5, 1, 1.5, 2, 3, and 4.

[0018] The beneficial effects of this invention are as follows: By incorporating fins within the heat exchanger, the thermal conductivity of the heat exchanger is enhanced, and heat is transferred to the hot-end distributor to enable the thermoelectric module to generate electricity. Hollow and heat-conducting channels are used to balance heat transfer and pressure drop of the exhaust gas. A baffle at the tail end of the flow pipe redirects the exhaust gas flow, enhancing heat transfer and temperature uniformity in the rear region. By using multiple flow pipes at different locations and forming bypass channels between them, the exhaust gas can flow between the heat-conducting and hollow channels, optimizing heat transfer efficiency, reducing pressure loss, and significantly improving the overall system performance.

[0019] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a cylindrical thermoelectric power generation system structure provided in an embodiment of the present disclosure; Figure 2 A front view of a cylindrical thermoelectric power generation system structure provided in an embodiment of this disclosure; Figure 3 A first internal structural cross-sectional view of a heat exchanger provided in an embodiment of this disclosure; Figure 4 A second internal structure cross-sectional view of a heat exchanger provided in an embodiment of this disclosure; Figure 5 This is an assembly diagram of a hot-end shunt and a cold-end shunt provided in an embodiment of the present disclosure; Figure 6 This is a schematic diagram of the structure of a cold-end shunt provided in an embodiment of the present disclosure; Figure 7 This is a schematic diagram of a first structure of a cooling channel provided in an embodiment of the present disclosure; Figure 8 This is a schematic diagram of a second structure of a cooling channel provided in an embodiment of the present disclosure; Figure 9 This is a schematic diagram of the structure of a thermoelectric module provided in an embodiment of this disclosure.

[0023] In the picture: 1. Heat exchanger; 2. Hot end distributor; 3. Cold end distributor; 4. Thermoelectric module; 5. Cooling pipe; 6. Fin; 7. Hollow flow channel; 8. Baffle; 9. P-type thermoelectric arm; 10. N-type thermoelectric arm; 11. Metal electrode plate; 12. Ceramic substrate; 13. Bypass channel; 14. Cooling channel; 15. Water inlet; 16. Water outlet. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Research has found that although traditional thermoelectric power generation technology can convert heat energy into electrical energy, the high speed of automobile exhaust means that most of the heat in the exhaust cannot be fully utilized before it is discharged, resulting in low thermoelectric conversion efficiency and poor practical performance.

[0026] Therefore, it is urgent to design a cylindrical thermoelectric power generation system structure and optimization method to solve the technical problem that most of the heat in the exhaust gas cannot be fully utilized before being discharged, resulting in low thermoelectric conversion efficiency and poor actual use effect.

[0027] The shortcomings of the above solutions are the result of the inventor's practical experience and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this disclosure below should be considered as the inventor's contribution to this disclosure.

[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the embodiments and features described below can be combined with each other. Furthermore, in the accompanying drawings, the thickness of components may be exaggerated or reduced for the purpose of effectively describing the technical content.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] Based on the above research, and referring to Figure 1This disclosure provides a cylindrical thermoelectric power generation system structure, including: a heat exchanger 1, a hot-end splitter 2, a cold-end splitter 3, and a thermoelectric module 4. The heat exchanger 1 is cylindrical with tapered ends to facilitate connection to the vehicle's exhaust pipe and reduce pressure generated by exhaust gas flow. The heat exchanger 1 has an inner radius of R4 and a length of L2. The inner radius of the tapered ends of the heat exchanger 1 is R1, and the outer radius is R2, meaning the thickness of the heat exchanger 1 is R2-R1. The hot-end splitter 2 has an inner cylindrical shape and an outer disc shape, and is installed on the outer wall of the heat exchanger 1. After the exhaust gas enters the heat exchanger 1, the high-temperature exhaust gas heats the heat exchanger 1, causing the heat exchanger 1 to conduct heat and heat the hot-end splitter 2. The inner cylindrical shape of the hot-end splitter 2 has a length of L7, a thickness of δ1, and an inner diameter equal to the inner diameter of the heat exchanger 1, ensuring that the hot-end splitter 2 completely fits the heat exchanger 1. The outer radius of the hot-end shunt 2 is R3. The difference between the outer and inner diameters of the hot-end shunt 2, i.e., the width of the hot-end shunt 2, is R3 + R1 - R2 - R4. The cold-end shunt 3 is installed on one side of the hot-end shunt 2, and the thermoelectric module 4 is installed between the hot-end shunt 2 and the cold-end shunt 3. The hot end face of the hot-end shunt 2 and the cold end face of the cold-end shunt 3 face the thermoelectric module 4 respectively, so as to generate a temperature difference on both sides of the thermoelectric module 4, thereby driving the thermoelectric module 4 to generate electricity. The length of the cold-end shunt 3 is L1, the width is W1, and the thickness is δ2.

[0031] Reference Figure 3 and Figure 4 In at least one embodiment, a flow pipe is installed inside the heat exchanger 1. The flow pipe is also cylindrical, meaning that a hollow flow channel 7 is formed through the flow pipe along its axial direction. The flow pipe coincides with the axis of the heat exchanger 1 so that the exhaust gas can pass through the hollow flow channel 7 after entering the heat exchanger 1. The outer diameter of the flow pipe is D2, the inner diameter is D1, and the length is L3.

[0032] Reference Figure 1 , Figure 2 and Figure 5 To improve power generation efficiency, several thermoelectric modules 4 are circumferentially attached to the sidewalls of the outer disk of the hot-end shunt 2 from both sides to maximize the utilization of the sidewall space of the hot-end shunt 2. Simultaneously, several cold-end shunts 3 are attached to the side of the thermoelectric modules 4 away from the hot-end shunt 2. At this point, the hot end face of the hot-end shunt 2 and the cold end face of the cold-end shunt 3 are respectively attached to both sides of the thermoelectric module 4 to achieve maximum power generation efficiency. Preferably, each hot-end shunt is combined with sixteen thermoelectric modules 4 and sixteen cold-end shunts 3 to form an integrated power generation system. Furthermore, four subsystems can be installed on one heat exchanger 1.

[0033] Reference Figure 3 and Figure 4In some embodiments, the heat exchanger 1 has several flow tubes inside, preferably four, with each flow tube equally spaced along the interior of the heat exchanger 1. Simultaneously, the outer wall of each flow tube has several fins 6, which are spaced circumferentially along the flow tube. The outer ends of the fins 6 are attached to the inner wall of the heat exchanger 1 to position and support the flow tubes. Furthermore, the fins 6 extend axially along the flow tubes, forming heat-conducting channels between adjacent fins 6. Through this arrangement, the internal space of the heat exchanger 1 is divided into heat-conducting channels and hollow channels 7. After the exhaust gas enters the heat exchanger 1, it can flow through both the heat-conducting channels and the hollow channels 7 simultaneously when passing through the flow tubes, thus balancing the heat transfer performance and pressure drop of the exhaust gas as it flows within the heat exchanger 1. Moreover, the design of the fins 6 significantly increases the heat transfer surface area inside the heat exchanger 1, improving the heat conduction efficiency, i.e., improving the heat transfer efficiency to the hot-end distributor 2. The length of fin 6 is L4, the difference between the outer diameter and the inner diameter, i.e. the width, is R3-D2 / 2, and the distance between the corresponding positions of fins 6 in two adjacent flow tubes is d5.

[0034] Reference Figure 3 and Figure 4 In at least one embodiment, a baffle 8 is installed at the tail end of at least one of the flow pipes, and the baffle 8 closes the hollow flow channel 7 of the flow pipe. When the exhaust gas flows through the baffle 8, the baffle 8 blocks the exhaust gas from passing through, so that the exhaust gas can only pass through the heat-conducting flow channel on the outside of the flow pipe corresponding to the baffle 8, thereby guiding the exhaust gas to enhance local heat transfer and temperature uniformity. The thickness of the baffle 8 is δ3, and its diameter is equal to the diameter D1 of the flow pipe. The baffle 88 can enhance the heat transfer and temperature uniformity of the rear region of the heat exchanger 1 by redirecting the exhaust flow.

[0035] Reference Figure 4 In at least one embodiment, a plurality of flow pipes are arranged at equal intervals along the interior of the heat exchanger 1, so that a bypass channel 13 is formed between two adjacent flow pipes. When the exhaust gas passes through the bypass channel 13, it can flow between the heat-conducting channel and the hollow channel 7, thereby reducing exhaust gas pressure loss, optimizing heat transfer efficiency, and significantly improving the overall performance of the system.

[0036] Reference Figure 6 and Figure 7 In at least one embodiment, a cooling pipe 5 is provided on the outside of the heat exchanger 1, and the cooling pipe 5 is adapted to allow coolant to flow through it. The cold-end distributor 3 has a cooling channel 14 inside, and the cooling channel 14 is connected to the cooling pipe 5. Furthermore, by aligning multiple cold-end distributors 3 and connecting them sequentially to each cold-end distributor 3 via the cooling pipe 5, it is possible to simultaneously connect multiple cold-end distributors 3 in parallel to the cooling pipe 5, thereby enabling the cooling pipe 5 to synchronously supply coolant to multiple cooling distributors.

[0037] Reference Figure 6 andFigure 7 In at least one embodiment, the cooling channel 14 circumferentially covers the cold end face of the cooling distributor. The cooling channel 14 has an inlet 15 and an outlet 16 at each end, which are respectively connected to the cooling pipe 5. The cooling pipe 5 has a length of L9 and includes several connectors. Each connector has a length of L8, an inner radius of R5, an outer radius of R6, and a thickness of R6-R5. The cold end distributor 3 is mounted on the connector, and the inlet 15 and outlet 16 are respectively connected to the connector.

[0038] Reference Figure 8 In at least one embodiment, the cooling channel 14 is serpentine, and the inner diameter of the cooling channel 14 is D3. Figure 8 Taking the direction as an example, the distance from the cooling channel 14 to the top and bottom of the cold end distributor 3 is d1, the distance from the cooling channel 14 to the left and right ends of the cold end distributor 3 is d4, the vertical distance inside the cooling channel 14 is d2, and the horizontal distance inside the cooling channel 14 is d3. This ensures that the cold end distributor 3 fully cools the cold end surface of the thermoelectric module 4 and makes the cold end temperature distribution of the thermoelectric module 4 uniform.

[0039] Reference Figure 9 In at least one embodiment, the thermoelectric module 4 includes a plurality of P-type thermoelectric arms 9, N-type thermoelectric arms 10, metal electrode plates 11, and two ceramic substrates 12. The P-type thermoelectric arms 9 and N-type thermoelectric arms 10 are arranged in an array and are staggered. The two ends of the metal electrode plates 11 are respectively connected to adjacent P-type thermoelectric arms 9 and N-type thermoelectric arms 10. The two ceramic substrates 12 are respectively located on both sides of the P-type thermoelectric arms 9 and N-type thermoelectric arms 10 and are attached to the metal electrode plates 11. The cross-section of the ceramic substrates 12 is square with a side length of L5, and the length of the metal electrode plates 11 is L6. Optionally, the thermoelectric module 4 includes one hundred and twenty-seven P-type thermoelectric arms 9 and one hundred and twenty-seven N-type thermoelectric arms 10, and two hundred and fifty-four metal electrode plates 11 for connecting the P-type thermoelectric arms 9 and N-type thermoelectric arms 10.

[0040] Furthermore, this disclosure also provides an optimization method for a cylindrical thermoelectric power generation system structure, applied to optimize the cylindrical thermoelectric power generation system structure as described above. The optimization method includes the following steps: Step S1: Assemble the cylindrical thermoelectric power generation system structure and arrange several flow pipes at equal intervals along the axial direction in the heat exchanger 1. Step S2: Based on its structural configuration and symmetrical heat transfer characteristics, a calculation model is established for a local structure to improve efficiency. Step S3: Set boundary conditions to simulate the theoretical operating state; Step S4: Install baffles 8 at the tail end of the flow pipe at different positions in sequence, establish corresponding control groups, calculate the net output power of each control group, compare the calculation results, and obtain the optimal installation position of baffle 8. Step S5: Set the height ratio of fin 6 to hollow flow channel 7 to R, replace fin 6 and flow pipe with different R values ​​in sequence, establish corresponding control groups, calculate the net output power of each control group, compare the calculation results, and obtain the optimal height ratio R of fin 6 to hollow flow channel 7.

[0041] The height ratio refers to the ratio of the difference between the inner diameter of heat exchanger 1 and the outer diameter of hollow flow channel 7 to the inner diameter of hollow flow channel 7.

[0042] In step S3, the boundary conditions for numerical optimization are set as shown in Table 1: Table 1 Boundary conditions for numerical optimization In step S4, the control group settings for the baffle 8 position and the impact of different baffle 8 positions on the net output power are shown in Table 2: Table 2. Influence of net output power on baffles at different positions The specific locations of positions 1-5 in Table 2 are referenced. Figure 4 As shown, position 0 refers to the case where no baffle is set.

[0043] As shown in Table 2, the introduction of baffle 8 significantly increases the exhaust pressure drop on heat exchanger 1, and as baffle 8 moves from position 0 to position 5, the output power initially increases, then decreases after exceeding position 3, so the net output power reaches its maximum at position 3.

[0044] In step S5, the R-value control group setting and the impact of different R-values ​​on net output power are shown in Table 3: Table 3. Effect of different R values ​​on net output power The height ratio R of fins 6 to hollow channels 7 has a significant impact on the optimal output performance of the cylindrical thermoelectric power generation system. A higher R significantly increases the convective heat transfer surface area between the exhaust gas and heat exchanger 1, thereby improving heat transfer efficiency. Conversely, a lower R increases the hollow channel 7, and changes in R severely affect the flow distribution between the hollow channel 7 and the finned channel 6, regulating convective heat transfer and pressure drop behavior. As shown in Table 3, when R increases from 1 to 1.5, the output power shows a moderate increase; above 1.5, the output power remains relatively stable until R=4. The exhaust pressure drop shows an inverse trend with the output power, decreasing continuously from R=0.5 to R=1.5, and then stabilizing. The high pressure drop at low R is due to the significant obstruction of the exhaust gas flow by the baffle 8. As R increases, the heat-conducting channel becomes the main exhaust channel, reducing flow resistance and stabilizing the pressure drop. The net output power increases significantly with R, reaching a peak at R=1.5 before stabilizing.

[0045] Therefore, based on the optimization results, it can be concluded that when the baffle 8 is in the middle position and the height ratio R of the fins 6 to the hollow flow channel 7 is 1.5 times, the optimal configuration with the maximum net output power and efficiency can be obtained. This configuration effectively balances heat transfer and pressure drop, resulting in the best system performance.

[0046] In the several embodiments provided in this application, it should be understood that It is understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Based on the above-described ideal embodiments of the present invention, and through the above description, those skilled in the art can make various changes and modifications without departing from the technical spirit of the disclosed embodiments. The technical scope of the embodiments of this disclosure is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A cylindrical thermoelectric power generation system structure, characterized in that, include: The heat exchanger (1) is hollow inside and suitable for the flow of exhaust gas; A flow pipe is arranged axially inside the heat exchanger (1); A hot-end splitter (2) is installed on the outer wall of the heat exchanger (1) and corresponds to the flow pipe; A cold-end splitter (3) is installed on one side of the hot-end splitter (2); Thermoelectric module (4) is installed between the hot end splitter (2) and the cold end splitter (3); The outer wall of the flow tube has several fins (6), and the outer ends of the fins (6) are attached to the inner wall of the heat exchanger (1). The flow pipe has a hollow flow channel (7) along the axial direction of the heat exchanger (1). The fins (6) are spaced apart along the circumference of the flow tube so that a heat conduction channel is formed between two adjacent fins (6); In addition, when the exhaust gas enters the heat exchanger (1), the flow pipe and fins (6) guide the heat of the exhaust gas through the heat exchanger (1) to heat the hot end face of the hot end splitter (2), so that the cold end face of the cold end splitter (3) and the hot end face of the hot end splitter (2) form a temperature difference with the two sides of the thermoelectric module (4), thereby driving the thermoelectric module (4) to generate electricity. The exhaust gas flows through the hollow flow channel (7) and the heat-conducting flow channel and exits the heat exchanger (1) to balance the heat transfer and pressure drop of the exhaust gas.

2. The cylindrical thermoelectric power generation system structure as described in claim 1, characterized in that, The heat exchanger (1) has several flow tubes inside, and at least one of the flow tubes is equipped with a baffle (8) at the tail end, which closes the hollow flow channel (7) of the flow tube. When the exhaust gas flows through the baffle (8), the baffle (8) blocks the exhaust gas from passing through, so that the exhaust gas can only pass through the heat-conducting flow channel outside the flow pipe corresponding to the baffle (8), thereby guiding the exhaust gas to enhance local heat transfer and temperature uniformity.

3. The cylindrical thermoelectric power generation system structure as described in claim 1, characterized in that, Several flow pipes are arranged at equal intervals inside the heat exchanger (1) so that a bypass flow channel (13) is formed between two adjacent flow pipes. When the exhaust gas passes through the bypass channel (13), it can flow between the heat-conducting channel and the hollow channel (7) to reduce exhaust gas pressure loss and optimize heat transfer efficiency.

4. The cylindrical thermoelectric power generation system structure as described in claim 1, characterized in that, A cooling pipe (5) is provided on the outside of the heat exchanger (1), and the cooling pipe (5) is suitable for the flow of coolant. The cold end splitter (3) has a cooling channel (14) inside, and the cooling channel (14) is connected to the cooling pipe (5).

5. The cylindrical thermoelectric power generation system structure as described in claim 4, characterized in that, The cooling channel (14) covers the cold end face of the cooling distributor in the circumferential direction.

6. The cylindrical thermoelectric power generation system structure as described in claim 4, characterized in that, The cooling channel (14) has an inlet (15) and an outlet (16) at its two ends, respectively. The inlet (15) and outlet (16) are respectively connected to the cooling pipe (5).

7. The cylindrical thermoelectric power generation system structure as described in claim 1, characterized in that, The thermoelectric module (4) includes several P-type thermoelectric arms (9), N-type thermoelectric arms (10), metal electrode plates (11) and two ceramic substrates (12). The P-type thermoelectric arm (9) and N-type thermoelectric arm (10) are arranged in an array, and the P-type thermoelectric arm (9) and N-type thermoelectric arm (10) are staggered. The metal electrode plate (11) is connected to the adjacent P-type thermoelectric arm (9) and N-type thermoelectric arm (10) at both ends respectively. The two ceramic substrates (12) are located on both sides of the P-type thermoelectric arm (9) and the N-type thermoelectric arm (10), respectively, and are attached to the metal electrode plate (11).

8. An optimization method for the structure of a cylindrical thermoelectric power generation system, characterized in that, The optimization method, applied to optimizing the structure of the cylindrical thermoelectric power generation system as described in any one of claims 1-7, comprises the following steps: Step S1: Assemble the cylindrical thermoelectric power generation system structure and arrange several flow pipes at equal intervals along the axial direction in the heat exchanger (1); Step S2: Based on its structural configuration and symmetrical heat transfer characteristics, a calculation model is established for a local structure to improve efficiency. Step S3: Set boundary conditions to simulate the theoretical operating state; Step S4: Install baffles (8) at the tail of the flow tube at different positions in sequence, establish corresponding control groups, calculate the net output power of each control group, compare the calculation results, and obtain the optimal baffle (8) installation position. Step S5: Set the height ratio of fin (6) to hollow channel (7) to R, replace fins (6) and flow pipes with different R values ​​in sequence, establish corresponding control groups, calculate the net output power of each control group, compare the calculation results, and obtain the optimal height ratio R of fin (6) to hollow channel (7).

9. The optimization method for the cylindrical thermoelectric power generation system structure as described in claim 8, characterized in that, The R-value control groups were set at 0.5, 1, 1.5, 2, 3, and 4.

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